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The 2.8 angstrom resolution atomic structure of the annexin XII hexamer reveals a 210K homohexamer with 3-2 symmetry in the asymmetric unit. The 70-angstrom-thick hexamer forms a concave disk with a diameter of 100 angstroms. Six Ca2+ ions are present in the hexamer formation. A novel model for annexin-phospholipid bilayer interaction indicates that Ca2+ sites present on the perimeter of the hexamer regulate the hydrophilic insertion of the protein complex into the phospholipid layer.

The temporary tethering of the selectins to the blood vessel wall leukocytes flowing in the bloodstream follows a first-order kinetics which indicates an unimolecular interaction between P-selectin and its glycoprotein ligand. The selectins slow their flow rate through the temporary tethering, with frequency dependent on the P-selectin site density. The high tensile strength of the P-selectin-to-ligand bond combined with the fast on and off bond rates and cytoskeleton anchoring allow for selectin-mediated rolling at physiological shear stresses when the leukocytes suffer hydrodynamic drag forces.

Carbon 70 (C70), a fullerene molecule, can effect electron transport more efficiently than previous artificial molecules due to its ability to act as a photosensitizer. C70 thus uses light to cause donor molecules to give up electrons. Moreover, C70 is a significant improvement over earlier mediators of electron transport because it can move electrons across a lipid bilayer membrane. These properties endow C70 and future fullerenes with great promise as transmembrane electron-transport systems.